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<h3>Concentration units</h3>
<p>
<ul>
<li>
<p><b>molal</b> is a unit for concentration =
 <nobr>moles / (kg of water)</nobr></p>

<p>Molality is therefore a concentration unit that is temperature- and
pressure-independent.</p>

<li>
<p><b>molar</b> = moles / (1L of aqueous solution),
is a concentration unit that is <nobr><i>T-</i></nobr> and <i>p-</i>dependent.</p>
</li>
</ul></p>
<p>At 25&deg;C the density of dilute aqueous solutions is &asymp;1000&nbsp; g/L,
and molality &asymp; molarity; however the density varies with concentration, temperature, <i>etc.</i></p>

<p>See also:
<ul><li><a href="SP_Activity.htm">activity</a></li>
<li><a href="SP_Ionic_Strength.htm">ionic strength</a></li></ul</p>

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